This invention relates to computer and electronic components and, more particularly, to sound card circuit configurations and related components for generating or processing audio signals, and, even more particularly, to a switching header connector and systems for generating or processing audio signals employing same.
Sound cards are add-on boards that are employed within a personal computer or related device to produce or process audio signals for enhancing sound quality, or for enabling sound capabilities, of the computer. Sound cards may, for example, produce or enhance a sound representing a prompt or other sound from an ordinary computer program, sounds for video games played on the computer, and downloadable music or sounds such as, for example, in an MPEG Audio Layer standard. Conventional sound cards may also be capable of capturing and processing signals from musical instruments.
The circuitry of a conventional sound card may include audio subsystems for digital audio capture and replay, as well as music synthesis, by, for example an internal FM synthesizer and playing a digitized or sampled sound. A matched pair of digital-to-analogue (DAC) and analogue-to-digital (ADC) converters coupled with a programmable sample rate generator may be provided to process digital audio.
In addition to an interface with the computer bus, sound cards typically provide an interface to a player that is capable of playing music and/or video, such as compact discs and digital video disks, which will be referred to herein as CD-ROMS. They also support proprietary interfaces for the CD-ROM player, as well as standard interfaces such as SCSI and IDE/EIDE standards. Thus, a sound card may process signals from CD-ROMS or other play-back equipment, downloaded or stored files (including telephone answering machine files), musical instruments, and the like.
Several connectors may be part of a sound card to provide digital or analog connections thereto. Such connectors include one or more microphone in connector(s), line in and line out connector(s), loudspeaker out connector(s), musical instrument digital interface (xe2x80x9cmidixe2x80x9d) port(s), joystick port, mpc-3 CD audio in or similar connector(s), auxiliary in connector(s), telephone answering device in connector(s), digital out connector(s), optical or coaxial digital I/O card connector(s), headphone outs connector(s), and the like.
Some of the connectors may be accessible from outside of the computer. Specifically, the headphone connector or headphone jack typically protrudes through or is accessible through an aperture in the sound card bracket, which encloses the expansion slot. The sound card circuitry may be configured such that the audio signal to the loudspeaker output connector(s) is muted in response to inserting a headphone plug into the headphone connector. In such a configuration in which the audio signal is audible through loudspeakers electrically connected to the loudspeaker output connector, plugging the headphone plug into the headphone connector stops the sound emitted from the loudspeakers in favor of providing the audio signal to the headphones.
Some computer manufacturers have placed a headphone jack at a location that is convenient to the user, such as the computer front panel. To connect it to the audio signal, the front headphone jack may be connected to the sound card. However, merely connecting the front headphone jack in parallel with the rear headphone jack would make it difficult to mute the audio signal in response to insertion of the front headphone connector into the front headphone jack. In this regard, although a general purpose input/output device may be employed to sense insertion of a headphone connector into the front headphone jack to mute the rear headphone jackxe2x80x94either through the card software or through an additional analog switchxe2x80x94such a configuration requires the use of additional op-amps and switches or custom sound card software, which increases cost and complexity of the sound card.
On the other hand, connecting the front headphone jack to a normally-open front connector on the sound card in series with the primary connector has the disadvantage that the signal must be transmitted to the front of the computer and back to the sound card during operation with the rear headphone jack or the loudspeakers. Further, because not all computer manufacturers employ a front headphone jack in addition to the rear headphone jack, sound card manufacturers must produce two versions of the same sound card. Computer manufacturers and sound card re-sellers and retailers likewise must keep two versions of each sound card in stockxe2x80x94one for use with computers employing only a single (that is, rear) headphone jack and another for use with computers having both a rear and front headphone connector. Similar problems are presented for a card having a microphone input connector in circumstances in which a second or front microphone connector is optionally provided and is to be spaced apart from the card.
A switching connector header and a sound card and related method that employ the connector header are provided. The switching features of the connector header enable the sound card to operate in both a first configuration and a second configuration. The first configuration includes a sound source (such as a sound processing circuit) the connector header, and a primary connector (such as a headphone jack disposed at a rear of a computer). An audio signal from the sound source passes through a normally-closed switch in the connector header to the primary connector and optionally to a main audio output contact. The second configuration includes, in addition to the components of the first configuration, a secondary connector, such as a headphone jack disposed at a front of the computer, having a wiring harness and a plug. Upon insertion of the wiring harness plug into the connector header, the header switches open to provide the audio signal to the secondary connector and optionally also to the primary connector.
The connector header according to a first aspect of the present invention is provided comprising: a housing including a plug opening disposed therein; a first pin and a second pin, such that at least a portion of each one of the first pin and the second pin are at least partially disposed within the housing; and a spring contact that is mechanically coupled to the first pin and moveable between a closed position and an open position. In the closed position, the spring contact engages the second pin to electrically couple the first pin and the second pin together. In the open position, the spring contact is disengaged with the second pin. The spring contact moves from the closed position to the open position in response to insertion of a plug into the plug opening.
According to a second aspect of the present invention, an audio circuit and corresponding sound card are provided that include a main audio system and a secondary system, which may be remotely located relative to the main audio system. The main audio system may be operative alone (that is, without the secondary system) or with the secondary system connected to the main audio system. In this regard, the audio circuit and corresponding sound card are provided comprising a sound source for manipulating or receiving an audio signal, a primary connector electrically coupled to the sound source, a switching header comprising a first contact electrically coupled to the sound source output, a second contact electrically coupled to the primary connector, and a header switch between the header first contact and the header second contact.
The audio circuit optionally includes an auto-muting, secondary connector circuit (which constitutes the secondary system) that may comprise: a secondary circuit first contact that is electrically coupled to the header first contact; a secondary circuit second contact that is electrically coupled to the header second contact; and a secondary connector switch that is electrically coupled between the secondary circuit first contact and the secondary circuit second contact. The secondary connector switch is capable of muting the audio signal at the header second contact.
The header switch moves from a closed position to an open position between the header first contact and the header second contact in response to coupling of the secondary circuit to the header. The header switch is in the closed position between the header first contact and the header second contact while the secondary circuit is not coupled to the header to enable the audio signal to pass therethrough to the primary connector circuit. In this regard, the audio circuit and sound card provided are operable in either a first configuration (that is, without the secondary circuit coupled thereto) or a second configuration (that is, with the secondary circuit coupled thereto). The primary connector may include a primary switch that opens to mute the audio signal to the main output contact in response to insertion of a primary plug into the primary connector. The audio circuit and sound card may employ one or more channels.
According to another aspect of the present invention, a method is provided for optionally coupling a secondary connector to a sound card that is operable for processing an audio signal either without the secondary connector or with the secondary connector coupled thereto. The method comprises the steps of providing a sound card for processing an audio signal and, optionally, plugging a secondary connector into a switching connector header of the sound card. The header has at least two electrically spaced-apart contacts and a header switch disposed therein. A first one of the header contacts receives the audio signal, and a second one of the header contacts electrically is coupled to the primary connector. The header switch is closed between the header first contact and the header second contact to enable the audio signal to pass therethrough to a primary connector disposed on the sound card. The header switch opens between the header first contact and the header second contact to mute the audio signal at the primary connector.
Additional features and aspects of the present invention will be apparent to persons familiar with sound card and/or header technology in light of the present disclosure.